针对双级加速离子光学系统的设计，开展了栅极几何参数对离子光学系统性能影响的研究。采用质点网格法和蒙特卡罗碰撞法开展栅极关键几何参数对束流引出能力、束流发散角、交换电荷(CEX)离子的截获影响规律研究；另外，还开展了不同比冲下束流发散角、碰撞交换电荷离子的变化趋势研究。研究结果表明，屏栅孔径对束流引出能力、束流发散角、CEX离子截获电流以及鞍点电势都有影响，随着屏栅孔径的增加，束流引出能力、束流发散角和鞍点电势呈上升趋势。加速栅孔径的变化对CEX离子得能量分布有影响，随着加速栅孔径的增大，截获的高能CEX离子逐渐减少，而随着加速栅厚度的增加，束流发散角、CEX离子的截获数量和能量呈上升趋势。在8000 s比冲下，加速级间距的改变对束流引出能力影响较小。另外，比冲对离子光学系统性能也有影响，比冲越高，束流发散角越小，且加速栅截获的CEX离子也越少。

The goal of the study is to identify the effect of the grid geometry parameters on the performance of the ion optics design. The combination of particle-in-cell method and Monte-Carlo collision method is used to study the influence of the critical geometrical parameters on the beamlet current capability, beamlet divergence angle and capture of charge exchange (CEX) ions. Moreover, the variation trends of beam divergence angle and impingement CEX ion are also investigated under different specific impulse conditions. The results show that with the increase of the screen grid aperture radius, the beamlet current capability, beam divergence angle and saddle point potential are increased. An increase in the accelerator grid radius produces a decrease in impingement CEX ion current. The beamlet divergence angle and the impingement CEX ion current both increase with the incremental thickness of accelerator grid. When the specific impulse is 8000 s, the change of the acceleration stage gap has little effect on the beamlet current capability. In addition, the higher the specific impulse, the smaller the beam divergence angle and the fewer the impingement CEX ions.